But first the weapon had to be miniaturized so that the focusing mechanism could be tested in the field. Among other things, this meant identifying targets that were relatively “soft” and easily accessible. Not the White House, but Hoover Dam. Not the Cheyenne Mountain Operations Center, where NORAD was headquartered, but the Golden Gate Bridge. Not the Pentagon, but… Culpeper.

Wilson smiled, contemplating the damage he was going to do. It would be massive and clever, and come out of nowhere – like dry lightning on a clear day.

He was still immersed in his equations when he heard shouting on the docks. A few minutes later, a knock on his door confirmed his suspicions. “Hasan is pleased to inform you dock strike is over!” In four hours, they were under way.

He was asleep when the ship, having carved its way through the swell and chop of the Black Sea, hove into sight of Odessa. It was the slowing of the engines that woke him up. His heartbeat was synchronized to their vibrations, so that, when the engines slowed, it hit him like a heart attack, and jerked him wide awake.

He dressed quickly and went out on the deck, which was slick with rain. The city was barely visible behind a curtain of fog. Sea and sky bled into each other, producing a gray wash, a sort of maritime whiteout. Which was disappointing, because Odessa promised to be an interesting city. According to the captain, at whose table Wilson had sometimes dined, Odessa had once been the Soviet Union’s largest port. “This is so,” the captain told him, “because the water is warm year-round. Everywhere else, it’s locked in ice.”

Without the push of the engines, the ship seemed almost to be still. But that was an illusion. Styrofoam cups and cigarette butts trailed in their wake.

Wilson shifted from foot to foot.

Bo had left a reassuring message in the Draft folder of their Yahoo! account. Their friend in Odessa was aware of the dock strike in Istanbul, and would adjust his schedule accordingly. Relax, Bo wrote. Everything’s cool.

That’s what Wilson told himself, but he couldn’t shrug off his unease. He fingered the red capsule Hakim had given him in Baalbek, a capsule he kept taped under his shirt collar. It worked by chemical suffocation, denying oxygen to each of the body’s cells. It was a fast and violent way to die, but it wasn’t Wilson’s way.

Almost idly, he stripped the capsule from under his collar, and dropped it over the side.

He could see Odessa clearly now. The docks were right in the middle of the city, with the port authority headquartered in a huge ugly concrete structure, and obscuring “the Potemkin steps” beside it.

Wilson had read about the famous staircase in his guidebook and was anxious to see it. A broad flight of 192 steps cascading down the hillside to the Black Sea, the stairs were an architectural marvel, constructed to exaggerate normal perspective. From the base they were said to appear unimaginably steep, an effect achieved by their gradual narrowing from a width of sixty-eight feet at the bottom to forty feet at the top.

The steps were made famous in a scene in Eisenstein’s Battleship Potemkin. In the film, czarist troops open fire on the civilians of Odessa. A mother falls. A baby carriage careens down the steps, bouncing past one body after another, its innocent occupant bound for destruction. Blood is everywhere.

Good movie, Wilson thought. He looked forward to seeing the real thing.

Transit visas had been arranged, the sheets of paper already attached to their passports.

Wilson and his bodyguards were met at the foot of the gangway by a skinny guy with a bad complexion who introduced himself as Sergei. “Mr. Belov sends his apologies. He regrets that he cannot be here until tomorrow. His daughter performs in a-” He frowned, then moved his fingers as if playing a piano.

“Recital,” Wilson said.

“Yes!” Sergei agreed with enthusiasm. “Permit me,” he said, grabbing Wilson’s suitcase. This way.” Within ten minutes, they were through Customs, submachine guns and all. “Express line,” Khalid said. Zero giggled.

Half an hour later, they were checking into the first-class Hotel Konstantin.

Zero and Khalid were elated by the idea of a day at such a hotel, especially once they checked in and learned that their room had a Playstation 2 and a copy of Grand Theft Auto.

Wilson was glad, too, because he would spend a day in the same city as Irina. Despite his fantasies about her, he was pragmatic. He knew that the women on the website were glammed up for their photos and would look, in real life, rather different. Some looked like prostitutes to him, heavily made up and showing plenty of cleavage, although that might be a cultural difference. In contrast, Irina seemed demure, like a housewife in an old sitcom. Someone who would serve tea and grow flowers.

Wilson did not intend to call her or speak to her, but he was desperate to have a look.

At three o’clock, he sat at a tiny table in the Cafe Mayakovsky on Deribasovskaya Street. It was a large and busy room with perhaps a dozen waitresses – his own a heavyset pink-faced brunette. He ordered tea and while he waited, fixed his eyes on the double swinging doors through which the waitresses came and went from the kitchen, trays aloft. Each wore a lacy frill pinned to her hair, and a green-checked uniform with white apron. They moved with grace and efficiency, even the older and fatter ones, gliding between the crowded tables, avoiding one another with a kind of intuitive radar, bending the knee to serve the hot drinks and dainty pastries. To Wilson, whose brain sought order and pattern everywhere, it seemed almost choreographed in its rhythm and balance, and he watched it with pleasure.

Then he saw her.

She came through the swinging doors, heavy tray aloft, walking with the posture of a dancer. Wilson felt a spark of pure joy at the sight of her, probably, he thought, no more than the low-voltage shock of recognition. It was akin to the satisfaction of finding the pivotal equation, or fitting the last bolt into a construction.

She was more petite than he’d imagined, yet her body was curvaceous. He was glad to see that. Scientific studies proved a connection between the proportion of waist-to-hip size and fertility, a biological explanation of why men were attracted to such women. Unlike in her smiling photograph, her face was set in an expression of earnest concentration as she gracefully made her way through the crowded room to a table at the window.

He drank a second tea, watching Irina come and go from the kitchen.

Now she was clearing a table, hoisting her tray to her shoulder and then taking a moment to survey the area – for a customer wanting a check, for a new customer, for whatever waitresses look for – when her eyes caught his.

There was, of course, no sign of recognition on her part – he had not sent his own photograph. But he felt a quick sexual spark that took him by surprise. He held her gaze until she looked away. She was flustered and tripped on the leg of a table. Some silverware slid off her tray onto the floor and she knelt to pick it up.

He was tempted to help her.

Instead, he signaled his waitress and paid the bill, leaving a generous tip. Irina looked back his way once more, just before heading into the kitchen with her tray. This time, she smiled, and he returned the smile, and there was a band of sensation between them that was almost electric.

It occurred to him that he could wait outside the restaurant. Follow her home. Find a way.

But no, it wasn’t time. Not yet…